Brown brake dust

[keith of kent]

A year ago (13K miles) I had front discs and pads replaced by local Indie. Used genuine MB parts.
A few weeks later drove to Italy and straight away noticed brown not black dust on front wheels. Cleaned it off and after 100 miles or so it was back. Also noticed a barely perceptible vibration above approx 60mph.
Indie checked it out on my return no fault found but had never seen brown brake dust. Prior to the pad /disc replacement I would get light quantities of black dust as normal
My normal motoring does not involve much motorway work or long journeys so for the interim period not really noticed the dreaded dust. Also I hand wash the car myself weekly, do not used wheel cleaner acid.
I have just returned from a 2000 mile continental trip of which most was motorway and with lots of heavy rain. The front wheels are really brown. Again I have the very slight vibration. I have never experienced this in over 40 years of driving. I'm very light on brakes.
Has anyone else experienced this?
I have my own theory about what might be occurring but would like the opinions of others before I say what they are

Edited to say it's a 2010 E350 212 Sport estate 63K miles

 

[grober]

Everything points to the new brake pads fitted. Could be cheap replica parts that have found their way into the supply chain at some point- I will leave speculation to you as to where that might have occurred. If you are still unhappy change them for new parts which you source yourself directly from an MB dealer. perferrably a different one from last time! Inchcape do mail order

http://www.mercedes-benz-parts.co.uk/

 

[edc]

Personally I would t worry about the brake dust colour as long as the braking performance is good.